I just learned about a little conure at a rescue in Georgia who lived for 11 years in a cage with cedar chips on the bottom - cedar is POISONOUS. I'm guessing there was a grating so he couldn't eat it, but the fumes...made his feathers fall out. ALL OF THEM. The owners took him to the vet and said "oh he's a feather plucker" and left it at that, even though, let's see, oh: parrots
can't pluck their own heads...
Milo's at the beginning of this vid
Then there's the 17 year old who's going to college in a year who came onto a parrot forum saying he wants to get a parakeet or cockatiel and then rehome it when he goes to college, just so he can have one "for now".
Oh let's make it a three-for...a lady in Ireland went to the home of a parent of another kid in her kid's toddler group and there was a cage covered with a dirty bedsheet in the corner. The homeowner said, oh those are lovebirds, they're too noisy so we cover them. They uncovered it and the male was dead and rotting with maggots and the female was almost dead. The lady took the female and rehomed her, but couldn't report the neglect/abuse because she took the bird away and the owner dumped the cage, destroying the evidence.